Tool jig



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TOOL JIG 3 Sheets-Sheet 1 Filed Nov. '5, 1942 INVENTOR.

April 1946. F. w. KIUPPERSMITH 2,3973193 TOOL JIG Filed Nov. 5, 1942 3 sheets-sheet 2 INVENTOR.

FRED MK'aPPaasM/m BX Maya April 2, 1946. F. w. KUPPERSMITH I ,4

TOOL JIG Filed Nov. 5, 1942 3 Sheets-Sheqt 5 a ,1 f f F i\ i fi/f/ 1 I I 1' V// i 47 k I 6, a 1 14/ 7 III i H J IN V EN TOR.

FRED M KUPPf/PJM/Tb B KM47 I Patented Apr. 2, 1946 UNITED STATES PATENT OFFICE j r. 2,397,493 l r I TOOL JIG Fred W. Kuppersmith, Bloomingtorn Iii. -Applica'tion November 5, 1942, Serial No. 464,805

(cl. 7l-=-62.) i

2 Claims.

This invention relates to jigs, and more particularly to improvements in quick clamping, box type jigs. The embodiment disclosed is especially adapted for use in connection with drilling operations.

It is an object of the invention to provide a drill jig adapted to quickly clamp a workpiece to be drilled and to hold the workpiecefirmly during the drilling operation. The invention also contemplates an effective quick acting locking mechanism adaptable for use "in connection with a reversible jig, if desired.

It a particular object of the invention to provlde a jig and convenient locking means therefor, which will be cheap to manufacture, convenient in operation and which will not easily get out of order; also, wherein any desired resilient pressure may be applied in order to hold the work firmly, and the jig plates may easily be locked in position or released.

Further objects will be apparent from the s ecifi'cation and drawings: 1

In the drawings:

Fig. 1 is a side elevation of one embodiment of the invention and illustrates the jig frames in clamping position with the operating handle in a position resiliently to lock the plates onto a workpiece. The partially released positionof the handle is shown in dotted lines,

Fig. 2 is a bottom view of the embodiment shown in Fig. 1.

Fig. 3 is a fragmentary detailed sectional view taken on a line substantially corresponding to line 3-3 of Fig. 1, and illustrates the locking and.

. tensioni'ng mechanism.

Fig. 4 is a top View of the embodiment shown in Figs. 1 to 3, with the handle shown in open position in full lines and in locking position in dotted lines.

Fig. 5 is a sectional plan view taken on a line substantially corresponding to line 5-5 of Fig. 6.

Fig. 6 is a sectional elevational view through the jig frames and bushing plates and is taken on a line substantially corresponding to line 66 of Fig. 4, with the jig in open position to receive a workpiece therebetween.

' Fig. '7 is a side elevational view of the device partially in section and with the elements shown in closed and locked position.

Fig. 8 is a composite side and elevational View of a workpiece adapted to be clamped by the jig shown in Figs. 1 to '7.

Referring to the drawings in detail, the embodiment illustrated comprises a base I having upright guide posts or leader pins 2 secured theretion of drill holes in theworkpiece.

' The bushing plate in the present embodiment is provided with an axial hole 6a in which is seecured a work-clamping member 1., which latter is located on the plate by means or a stud 8 extending upwardl into the hole Ba. The clamping member '1 is provided with an axial upwardly extending bolt la shown by dotted lines, and may be secured in position by means of a flanged nut 9.

The base i is provided with a bushing plate Ill, which latter may be very similar to the plate 4 previously described, but which is inverted v in position and is provided withan anvil or mandrel l'l thereonywhic'h latter is mounted in a central bore l2 by means of a bolt and nut l3 in the same manner as the member Iv is secured in the upper bushing plate. This mandrel l l is adapted to receive and align a workpiece l4 thereon, which workpiece, in the present instance, is in the form of a heavy washer (see Fig. 8) and is shown in dotted lines on the mandrel H in Fig. 6. It will be understood that the construction of the workholding elements may be varied to conform with the workpiece requirements.

The lower bushing plate i0 is preferably provided with clearance bushings Ila (Fig. '5) which are mounted in suitable openings in the bushing plate, so as 'to' be in accurate alignment with the upper guide bushings Ii. 'It will be apparent that the workpiece [4 may be clamped between the mandrel or anvil H and the clamp member I by vertical movement of the upper frame assembly.

The opening and locking mechanism of the jig comprises an angle bracket l5 pivotally secured to the back of the base I by means of a pivot pin Hi. This pin is retained in a suitable bore IT by means of a set screw l8 engaging in an inclined notch la in the pin, as illustrated in Fig. 3. An operating arm or handle 20 is pivoted at 2| on a bar 22 depending from the upper frame 3 and secured thereto by means of a machine screw 23. The handle or lever 20 is provided with a short upwardly extending arm 24, and ,2. depending angle bracket 25 is pivotally secured thereto at 26. The outwardly extending arms 25a and 15a of the brackets 25 and I5, respectively, are in alignment as shown in Fig. 3. A guide bushing 21 is mounted in the bracket arm 25a and the arms are secured together by means of a bolt 29, which latter extends through the brackets and bushing and retains a spring 30 under a pre determined compression against the upper arm 25a by means of a washer 3| and nut 32. It will be apparent that the spring compression may be adjusted to retain the jig elements in clamping relationship at a' required pressure. A washer 29a is mounted on the bolt 29 and between the brackets to limit the closed position ,of the jig frames and to prevent injury to the work-holding and aligning elements;

The pivots 2i and 26 which movably secure the handle 20 and the upin' the position shown in frame and said upper frame and a hand lever pivotally secured to one of said frames for reciprocating said frames: the improvement which comprises a first bracket having an outwardly extending arm pivotally secured to one of said frames, a second bracket also having an outwardly extending arm pivotally secured directly to said hand lever at a point removed from the point at which the hand lever is pivoted to one of said frames, resilient means operating-between said outwardly extending arms tending to hold them together in clamped relationship thereby providing a resilient link connection between said base frame and said upper frame whereby said frames are in workpiece-securing position when the hand lever is in one position and in workper bracket 25 together and to the upper frame 3; I are so related that they provide a toggle mech Fig. l, the pivot 2'6 is slightly to the left 0f the dead center of the toggle mechanism. Therefore, the elements are held securely clamped by means of the compression spring. In thi position, a

. pin 20a on the handle engages the upper bracket and prevents further downward movement of the handle 20. When'the handle is raised to the'dotted line position, the pivot 26 is moved to v the oppositeside 'ofthe dead center line, as shown by the dotted lines, and therefore the pressure on the workpiece is relieved; Also, this movement of the handle may be continued until it is moved substantially 180 to the position shown in Fig. 6, so that the pivot 26 is moved to a position below the pivot 2| and therefore the upper frame 3 is raised to its fully open'position'. The drilled workpie'ce may then be removed and a fresh workpiece inserted. r

The controlling and locking mechanism ma be tially any box type jig without material change in any of the'elements or in the manner of assem- 1 my. V

It is intencled,'"of course, that the invention should not be limitedto the specific embodiment or embodimentsdisc'losed orto the exact details of constru'ctionsho'wn; as'obvious modifications will occur topersons' skilled in the art.

Having thus described this invention, what is claimed and desired to be. secured. by Letters Patentisr I 1 a 1. In a'quick-clamping tool jig of the character described including a'base frame an upper frame mounted for reciprocation'thereabove, means for firmly engaging aworkpiece between said base wvherebysaid frames'are in workpiece-securing position and wherein the pressure exerted to hold said workpiece is determined bythe tensioning of said resilient .means, and a stop member integral with said hand lever adapted to'abut against said second bracket to preventmovementof said hand lever in one direction out of workpiece-securing position. 7 j p,

2. In a quick-clamping tooljig of the character described including a base frame, an upper frame mounted for reciprocation thereabove, 'means for firmly engaging a workpiece between said base frame and said upper frame, and a hand lever pivotally secured to said upperframe for reciprocating said frame: the improvement'fwhich comprises a first vL-shap'ed bracket. having. an outwardly extending apertured arm pivotall se cured to said base frame, a second L-shaped bracket also having an outwardly extending apertured arm pivotally secured directly to said hand lever at a point removed from the pointat which the hand lever is pivoted to said upper frame, said arms being spaced from each other and having the apertures therein in-registeringlrelationship, means extending through said apertures'for securing said arms together, resilientfine'an's associated with said last-mentioned means tending to hold said arms together in clamped relationship thereby providing a resilient link connection between said base frame and said upper. frame position when the hand lever is in one position and in workpiece-releasing position when swung to another positionand wherein the pres'sure'exerted to hold said workpiece is determined by the tensioning of saidjresilient means,{and a'stop member integral with saidha'nd lever ad'aptedto abut against said second bracket to prevent movement of said hand lever in'one direction out of workpiece-securing position. i

FRED W. KUl PERSMI TH. 

